geo $country {
    ranges;
    default                   ZZ;
    127.0.0.0-127.0.0.0       US;
    127.0.0.1-127.0.0.1       RU;
    127.0.0.1-127.0.0.255     US;
    10.1.0.0-10.1.255.255     RU;
    192.168.1.0-192.168.1.255 UK;
}

location /whatever {
    deny  123.132.123.15/32
    deny  123.132.123.16/28
    deny  123.132.123.32/28
    deny  123.132.123.48/31
    deny  123.132.123.50/32;
    allow all;
}